1. Field of the Invention
The present invention is related to tocopherol derivatives and their salts, and to method for preparation thereof.
2. Description of the Related Arts
Cosmetics have the purpose of neatening and beautifying skin and hair, and giving nutrients and health to them. In particular, much research has been devoted recently to inhibiting fine wrinkles on skin through the activation of dermal cells. As a result, many materials have been developed. For example, it was reported that materials including vitamins such as retinol and ascorbic acid, proteins and flavonoid extracted from various plants and animals, amino acids, epidermal growth factor and xcex1-hydroxyl acid are effective in inhibiting fine wrinkles on the skin. Such materials are applied to cosmetics and the like. However, most of traditional materials effective on fine wrinkles of skin have defects including low stability of the effective ingredient and the like.
Further, it was reported that tocopherol, one of liposoluble-type vitamins, has bioactive functions including a protective function against activity of free radicals which are harmful to human body, promotion of cell growth, and induction of collagen biosynthesis, anti-allergy effects and anti-inflammatory effects. Therefore, tocopherol has also been used as a cosmetic source because of its bioactivities. However, the unstable, liposoluble and water-insoluble properties of tocopherol have limited the uses of tocopherol as a cosmetic source.
Recently, many tocopherol derivatives have been developed in order to improve its stability. For example, U.S. Pat. No. 4,564,686 disclosed that compounds produced by phosphatic esterification between tocopherol and ascorbic acid could improve the stability of tocopherol. However, the traditionally known tocopherol derivatives could improve only the stability of tocopherol. And they were materials combined simply through the esterification between tocopherol and compounds with similar physiological activities. However, tocopherol derivatives introduced with compounds with other physiological activities have still not been developed.
Under these circumstances, the present inventors have conducted much research to prepare tocopherol derivatives into which compounds with other physiological activities may be introduced, so that other bioactivities and improved stability of tocopherol can be obtained thereby. As a result, it was found that the tocopherol derivatives introduced with 3-aminopropane phosphate could be hydrolyzed through biological enzymes in a living body, and the tocopherol-hydrolyzed products, tocopherol and 3-aminopropane phosphate, can perform different physiological activitives. In addition, these tocopherol derivatives have both hydrophilic and hydrophobic groups, thus show improved stability in aqueous mediums. And these tocopherol derivatives also show a much more improved anti-oxidative effect than tocopherol.
Thus, an object of the present invention is to provide the tocopherol derivatives represented by the following formula (I), and their salts: 
Wherein,
R1, R2 and R3 are H or methyl group, and at least one positions selected from group consisting of the R1, R2 and R3 positions are methyl group; and,
A is CH2xe2x80x94CH(CH3)xe2x80x94 or CHxe2x95x90C(CH3)xe2x80x94
The other object of the present invention is to provide a method for preparing the above tocopherol derivatives. The tocopherol derivatives is prepared by reacting tocopherol with phosphorous oxychloride in an equivalent ratio of 1:1xcx9c1.3, in presence of an organic base, in an organic solvent; reacting the tocopherol dichlorophosphate produced by the above reaction with 3-aminopropanol in presence of an organic base, in an organic solvent; and, hydrolyzing the above products.
The tocopherol derivatives according to the present invention can be hydrolyzed by biological enzymes in a living body to produce tocopherol and 3-aminopropane phosphate. And they can induce physiological activities including recovery of injured skin, prevention from aging of bio-membrane, etc. Also, the tocopherol derivatives according to the present invention have improved stability, safety to skin and anti-oxidant effect superior to preceding tocopherol and its derivatives.